Noob question about OS

Hi All – I’ve decided to jump in and I’m getting 3x RTX 2060 6GB and onboard the PC has a Nvidia GTX 970 (I know, an old card). I’ve got an i7 HP Envy PC that I’ll lift the motherboard out of (20 PCI Lanes). So, my question is … OS. I’m super-comfortable on Linux, so would probably like to not buy a windows 10 license. I know I’ll need a PCI-e splitter. Other information is I’ve got a 6 kWh solar setup and a 4 kWh battery as well. I think I can make far more from my solar by generating crypto than selling excess to the grid. Any thoughts or advice?

Thanks